-News from the <a href="http://www.shiningsilence.com/dbsdlog/">DragonFly Digest</a>

+DragonFly version 4.6 brings brings more updates to accelerated video for both i915 and radeon users, home-grown support for NVMe controllers, preliminary EFI support, improvements in SMP and networking performance under heavy load, and a full range of binary packages.

+

+Go to the [4.6 release page](release46) page for details, or [[download]] via one of the [[mirrors]].

+DragonFly belongs to the same class of operating systems as other BSD-derived systems and Linux. It is based on the same UNIX ideals and APIs and shares ancestor code with other BSD operating systems. DragonFly provides an opportunity for the BSD base to grow in an entirely different direction from the one taken in the FreeBSD, NetBSD, and OpenBSD series.

-The [[new 2.2 release|release22]] includes [[Hammer|hammer]], a filesystem that includes instant crash recovery,

-mirror data to other volumes. It has undergone extensive stress-testing and is considered production-ready!

+DragonFly includes many useful features that differentiate it from other operating systems in the same class.

-### Summer of Code participation

+The most prominent one is HAMMER, our modern high performance filesystem with built-in mirroring and historic access functionality.

-DragonFly [has been accepted](http://socghop.appspot.com/org/home/google/gsoc2009/dragonflybsd) to Google's Summer of Code for 2009, after a successful [[2008 session|docs/developer/GoogleSoC2008]]. If you're a student, start planning for entering your proposal on the 23rd. If you can mentor, please sign up at the [Google site](http://socghop.appspot.com/) and request a mentoring slot. There is [[an initial page|gsoc2009]] listing potential projects; please read and add to it if you are interested.

+Virtual kernels provide the ability to run a full-blown kernel as a user process for the purpose of managing resources or for accelerated kernel development and debugging.

-Check the [DragonFly Digest](http://www.shiningsilence.com/dbsdlog/) for other current events, or check the headlines listed on this page.

+The kernel makes extensive use of tokens as a synchronization mechanism; tokens are inherently deadlock-free and easily composable. The use of soft token locks results in less cross-subsystem pollution and more maintainable code, both of which allow us to parallelize the system with less effort compared to other kernels, which primarily use hard mutex locks.

+DragonFly is uniquely positioned to take advantage of the wide availability of affordable Solid Storage Devices (SSDs), by making use of swap space to cache filesystem data and meta-data. This feature, commonly referred to as "swapcache", can give a significant boost to both server and workstation workloads, with a very minor hardware investment.

+Some other features that are especially useful to system administrators are variant symlinks (i.e. symlinks that are resolved at runtime based on user-specific or system-wide variables) and a performant and scalable TMPFS implementation. Our system makes pervasive use of NULLFS mounts, which allow the administrator to make arbitrary parts of the filesystem hierarchy visible in other locations with virtually no overhead.

-DragonFly belongs to the same class of operating system as BSD and Linux

-and is based on the same UNIX ideals and APIs. DragonFly gives the BSD

-base an opportunity to grow in an entirely different direction from the one

-taken in the FreeBSD, NetBSD, and OpenBSD series.

-

-From 2003 (when DragonFly first forked from FreeBSD), to early 2007,

-the DragonFly project focused on rewriting most of the major kernel

-subsystems to implement required abstractions and support mechanics

-for the second phase of the project. This involved a great deal of work

-During all of this we have managed to keep the system updated with regards

-to the third party applications and base system utilities needed to make

-any system usable in production. We have also adopted the PkgSrc system for

-management of all non-base-system third-party applications in order to pool

-our resources with other BSD projects using the system.

-

-In the 2007-2008 time-frame a new filesystem called HAMMER was developed

-for DragonFly. HAMMER sees its first light of day in the July 2008

-2.0 release. This filesystem has been designed to solve numerous issues

-and to add many new capabilities to DragonFly, such as fine-grained

-snapshots, instant crash recovery, and near real-time mirroring.

-The filesytem is also intended to serve as a basis for the clustering

-work that makes up the second phase of the project.

-

-The second phase of the project is now upon us. The DragonFly project's

-ultimate goal is to provide native clustering support in the kernel.

-This involves the creation of a sophisticated cache management

-framework for filesystem namespaces, file spaces, and VM spaces, which

-allows heavily interactive programs to run across multiple machines with

-cache coherency fully guaranteed in all respects. This also involves being

-able to chop up resources, including the cpu by way of a controlled VM

-context, for safe assignment to unsecured third-party clusters over the

-internet (though the security of such clusters itself might be in doubt,

-the first and most important thing is for systems donating resources to not

-be made vulnerable through their donation).

+A major crux of any open source operating system is third party applications. DragonFly leverages the dports system to provide thousands of applications in source and binary forms. These features and more band together to make DragonFly a modern, useful, friendly and familiar UNIX-like operating system.

+The DragonFly BSD community is made up of users and developers that take pride in an operating system that maintains challenging goals and ideals. This community has no reservation about cutting ties with legacy when it makes sense, preferring a pragmatic, no-nonsense approach to development of the system. The community also takes pride in its openness and innovative spirit, applying patience liberally and always trying to find a means to meet or exceed the performance of our competitors while maintaining our trademark algorithmic simplicity.

+For more information, visit the [[Features|features]] and [[History|History]] pages.

+## Now Hiring

+DragonFly provides a welcoming environment for those looking to participate in open source. See the [[Projects|/docs/developer/ProjectsPage]], [[Research Projects|/docs/developer/ResearchProjectsPage]], [[Code Bounties|/docs/developer/Code_Bounties]] and [[Summer of Code Projects|/docs/developer/GSoCProjectsPage]] pages for project ideas. If you are looking for an easy way to get your feet wet, you might find something suitable in the [Bug Tracker](http://bugs.dragonflybsd.org/). Or bring up your own idea on the appropriate [[mailing list|mailinglists]] or IRC!